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Nikolaos P Polyzos – One of the best experts on this subject based on the ideXlab platform.

  • cumulative live birth rates and number of oocytes retrieved in women of advanced age a single centre analysis including 4500 women 38 years old
    Human Reproduction, 2018
    Co-Authors: Marta Devesa, Nikolaos P Polyzos, I Rodriguez, Buenaventura Coroleu, Francisca Martinez

    Abstract:

    STUDY QUESTION: Is there any relationship between the number of oocytes retrieved and cumulative live birth rates (CLBRs) in women of advanced age? SUMMARY ANSWER: CLBRs increase with the number of oocytes retrieved in women of advanced reproductive age up to 41 years old, the added value is minimal in women more than 41 years and futile in women 44 years or older. WHAT IS KNOWN ALREADY: CLBR is actually the most relevant outcome of IVF from patients’ perspective. There are several studies that have analysed CLBR’s but some of them have included several stimulation cycles, others have not included the frozen embryo transfers (FETs) in their analysis and none has focused on women of advanced reproductive age. We aimed to assess CLBR in women ≥38 years after a single stimulation cycle plus the subsequent frozen embryo transfers. STUDY DESIGN, SIZE, DURATION: This is a retrospective analysis carried out in a University-affiliated tertiary centre between January 2000 and December 2013. Overall, 4570 infertile women aged ≥38 years who underwent their first cycle in our centre were included. PARTICIPANT/MATERIALS, SETTING, METHODS: Patients were categorized in four age-groups: 38-39 years (G1 = 1875 cycles), 40-41 years (G2 = 1380 cycles), 42-43 years (G3 = 833 cycles) and ≥44 years (G4 = 482 cycles). CLBR’s were evaluated by adding the pregnancies and live births achieved in the FET’s to the ones obtained in the fresh cycle. In order to find out the actual effect of the number of oocytes retrieved in these patients, a predictive model of CLBR according to age and oocyte yield was built. MAIN RESULTS AND THE ROLE OF CHANCE: CLBRs significantly decrease with increasing age among women ≥38 years of age, with the most prominent and clinically relevant decline observed at 42-43 years old, and clear evidence for futility in women aged ≥44 years (25.9% at 38-39 years, 16.4% at 40-41 years, 7% at 42-43 years and 1.2% from 44 years onwards). The higher the number of oocytes retrieved, the higher the CLBR; however, this is more evident up to 41 years old and no clear benefit is observed from 44 years and beyond. LIMITATIONS, REASONS FOR CAUTION: Limitations are related to the retrospective nature of the study; however, no significant differences were observed in the treatment protocols used. Other potential limitations could be the fact that embryo cryopreservation was carried out with slow freezing in 80% of cases and that a small proportion of patients still have frozen embryos; nevertheless, we do not expect a relevant impact of these issues as slow freezing showed excellent results that did not differ significantly compared to vitrification and, on the other hand, the extra benefit coming from the FETs was very limited. WIDER IMPLICATIONS OF THE FINDINGS: The number of oocytes retrieved is significantly associated with CLBR also in women of advanced reproductive age. However, the added benefit appears to be restricted mainly in women up to 41 years old. Women over 43 do not experience any benefit in CLBR irrespective of the number of oocytes retrieved, and thus should be discouraged from doing an IVF cycle with their own oocytes; for the other age-groups, recommendations should be given considering the age and the expected ovarian response. STUDY FUNDING/COMPETING INTEREST(S): None. TRIAL REGISTRATION NUMBER: NA.

Jin Yang – One of the best experts on this subject based on the ideXlab platform.

  • 0d 2d and 3d metal phosphonates assembled from a new 2 carboxybiphenyl 4 ylmethylphosphonic acid syntheses topological structures and photoluminescent properties
    CrystEngComm, 2012
    Co-Authors: Jin Yang

    Abstract:

    A series of metal phosphonates, namely, [Cu(HL)(H2O)] (1), [Cu5(L)2(OH)4]·H2O (2), [Zn3(L)2(H2O)] (3), [Zn3(L)2(phen)2(H2O)2] (4), [Cd3(L)2(H2O)2] (5), [Cd2(L)(OH)(H2O)1.5] (6), and [Cd(HL)(phen)2]·2.5H2O (7), where H3L = 2′-carboxybiphenyl-4-ylmethylphosphonic acid, and phen = 1,10-phenanthroline, have been synthesized under hydrothermal conditions. Compound 1 exhibits a 2D layer structure with the 4-connected (42·64) topology. Compound 2 shows a 2D (3,10)-connected (32·6)(38·48·512·69·74·84) topology. Compound 3 displays a 2D (3,6)-connected (42·6)2(47·66·82) topology. Compound 4 is a 3D framework with the (42·6)2(47·66·82) topology. Compound 5 shows a 2D (4,6)-connected (44·62)(46)(410·65) topology. Compound 6 exhibits a 2D (3,6)-connected (42·6)(46·66·83) topology. Compound 7 displays a 0D closed loop structure. Furthermore, compounds 1, 5 and 7 are consolidated by the intramolecular O–H⋯O hydrogen bonds. All the compounds have been characterized by infrared spectra (IR), elemental analyses, powder X-ray diffraction (PXRD) and thermogravimetric (TG) analyses. The luminescent properties of 3–7 have also been studied.

  • 0D, 2D and 3D metal phosphonates assembled from a new 2′-carboxybiphenyl-4-ylmethylphosphonic acid: Syntheses, topological structures and photoluminescent properties
    CrystEngComm, 2012
    Co-Authors: Jian-fang Ma, Jin Yang

    Abstract:

    A series of metal phosphonates, namely, [Cu(HL)(H2O)] (1), [Cu5(L)2(OH)4]·H2O (2), [Zn3(L)2(H2O)] (3), [Zn3(L)2(phen)2(H2O)2] (4), [Cd3(L)2(H2O)2] (5), [Cd2(L)(OH)(H2O)1.5] (6), and [Cd(HL)(phen)2]·2.5H2O (7), where H3L = 2′-carboxybiphenyl-4-ylmethylphosphonic acid, and phen = 1,10-phenanthroline, have been synthesized under hydrothermal conditions. Compound 1 exhibits a 2D layer structure with the 4-connected (42·64) topology. Compound 2 shows a 2D (3,10)-connected (32·6)(38·48·512·69·74·84) topology. Compound 3 displays a 2D (3,6)-connected (42·6)2(47·66·82) topology. Compound 4 is a 3D framework with the (42·6)2(47·66·82) topology. Compound 5 shows a 2D (4,6)-connected (44·62)(46)(410·65) topology. Compound 6 exhibits a 2D (3,6)-connected (42·6)(46·66·83) topology. Compound 7 displays a 0D closed loop structure. Furthermore, compounds 1, 5 and 7 are consolidated by the intramolecular O–H⋯O hydrogen bonds. All the compounds have been characterized by infrared spectra (IR), elemental analyses, powder X-ray diffraction (PXRD) and thermogravimetric (TG) analyses. The luminescent properties of 3–7 have also been studied.

David A. Grant – One of the best experts on this subject based on the ideXlab platform.

  • current results of intestinal transplantation
    The Lancet, 1996
    Co-Authors: David M Grant, David A. Grant

    Abstract:

    Abstract Summary Background Intestinal transplantation is an alternative to total parenteral nutrition (TPN) for the treatment of chronic intestinal failure. To determine the current status of small-bowel transplantation, we have reviewed the world experience since 1985. Methods We built up an international registry by asking twenty-five intestinal transplantation programmes to submit standard data on their cases operated on between 1985 and June, 1995. Findings One centre (two transplantations) did not use our report form, and these cases were excluded. The remaining twenty-four programmes did 180 transplantations in 170 patients. Two-thirds of the recipients were children. The main indication (64%) was short-gut syndrome; another 13% had a tumour. Of the grafts, 38% were small-bowel with or without colon, 46% were intestine plus liver, and 16% were multivisceral. Graft/patients’ survival (%) at 1 and 3 years under cyclosporin immunosuppression was, respectively: 17/57 and 11/50 for small bowel only; 44/44 and 28/28 for intestine plus liver; and 41/41 and 41/41 for multiviscera. The corresponding figures under tacrolimus were: 65/83 and 29/47; 64/66 and 38/40; and 51/59 and 37/43. 78% of the 86 survivors had stopped TPN and resumed oral nutrition. Interpretation Our approach cannot give data on long-term outcome. The short-term results of intestinal transplantation are similar to those of lung grafting. We conclude that small-bowel transplantation has become a life-saving option for patients who cannot be maintained on TPN and for those who require massive abdominal evisceration for locally aggressive tumours.